Attention and Visual Perception • 95just cut in front of him, traveling 70 miles per hour on the highway. The question to ask
yourself is, would you be having the same conversation if you were a passenger sitting
next to the driver? As a passenger, you would be aware of the traffi c situation and would
be able to react by pausing the conversation or perhaps warn the driver of upcoming
hazards (This is sometimes called “backseat driving”!). It is also relevant to consider the
social demands of phone conversations. Because it is generally considered poor form to
suddenly stop talking or to pause for long periods, the person talking on the phone while
driving might continue talking even when driving is becoming challenging.
An interesting phenomenon related to cell phone use is revealed by the results
of a 2008 survey by Nationwide Mutual Insurance, which found that even though
an overwhelming majority of people who talk on cell phones while driving consider
themselves safe drivers, 45 percent of them reported that they had been hit or nearly hit
by another driver talking on a cell phone. Thus, people identify talking on cell phones
while driving as risky, but they think others are dangerous, not themselves (Nationwide
Insurance, 2008).
The main message here is that the distraction of attention associated with talk-
ing on a cell phone can degrade driving performance. And cell phones aren’t the only
attention-grabbing device found in cars. An article in the New York Times titled “Hi,
I’m Your Car. Don’t Let Me Distract You,” notes that many new cars have distraction-
producing devices such as GPS navigation systems and menu screens for high-tech
computer controls (Peters, 2004). Because these devices require attention and time
(an average of 5.4 seconds to read and process electronic maps, for example), these
distractions could, like cell phone use, also be contributing to unsafe driving by caus-
ing drivers to glance away from the road. Recently, with more people beginning to
send text messages while driving, a study by the Virginia Tech Transportation Institute
found that truck drivers who send text messages while driving are 23 times more
likely to cause a crash or near crash than truckers who are not texting (Hanowski
et al., 2009).Attention and Visual Perception
It is clear that attention is an important component of many of the tasks we carry out
routinely every day. In this section we take this idea a step farther by describing experi-
ments that show that attention is so important that, without it, we may fail to perceive
things that are clearly visible in our fi eld of view.INATTENTIONAL BLINDNESS
One way to demonstrate the importance of
attention for perception is to create a situa-
tion in which a person’s attention is focused
on one task and then determining whether the
person perceived an easily visible nearby stim-
ulus. Arien Mack and Irvin Rock (1998) used
this procedure, as shown in ● Figure 4.17. The
observer’s task was to indicate which arm of
the cross was longer, the horizontal arm or
the vertical arm. Then, on one trial, a small
test object, which was within the observer’s
fi eld of clear vision, was added to the display.
When observers were then given a recognition
test in which they are asked to pick the object
that had been presented, they were unable
to do so. Paying attention to the vertical and● FIGURE 4.17 Inattentional blindness experiment. (a) On each trial,
participants judge whether the horizontal or vertical arm is longer. (b) After a
few trials, the inattention trial occurs, in which a geometric object is fl ashed
along with the arms. (c) In the recognition test, the participant is asked to
indicate which geometric object was presented. (Source: From E. B. Goldstein,
Sensation and Perception, 8th ed., Fig. 6.9, p. 139. Copyright © 2010 Wadsworth, a part of Cengage
Learning. Reproduced with permission. http://www.cengage.com/permissions.)Indicate longer arm:
horizontal or vertical?Which arm is
longer?Which object
did you see?Subject
seesSubject’s
taskInattention trial Recognition test3–4
more
trials
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